City thumped their FA Cup opponents 4-0 yesterday.
Mancini said: "I hope Sergio will be like this from now until the end, because if Sergio is like this, and our strikers continue to score a lot of goals from now until the end, I think the championship is not finished.
"This is possible but I think it should be confident, always. If we are 12 points behind - we lost seven points in three games. This can happen for every team. We play a lot of games.
"I think in this moment they deserve to be there because they played better than us. They scored more goals than us."